Worst thing that can happen with a chloroquine and azithromycin combination is that it causes heart arrhythmia and sudden death in a patient that would not have otherwise died.
Studies of patients taking this combination of meds include daily EKGs, which is something the general population at home isn't going to have access to.
https://twitter.com/search?q=azithromycin%20qt&src=typed_que...
I bet it can, if FDA is beat over the head with a shovel, which it will be if the need arises. It's a real ECG verifiably capable of detecting irregular hearth rhythm, and it costs a tiny fraction of what a big-ass ECG machine would, and therefore can be deployed at a much larger scale. Just because it could only get approval to detect atrial fibrillation duing "peacetime" doesn't mean it can't be pressed into service for other things.
Coughing your lungs out but feel like CNN is not lying to you? Easy! Refuse the drug. Nobody can force you to take it.